Integrated circuits (ICs) are now universally found in electronic products from cell phones to airplanes. Continuing progress in IC technology continues to lead to higher and higher levels of circuit integration. Part of the reason for this is the computer industry's relentless drive toward higher performance, lower cost, increased miniaturization, and greater packaging density of integrated circuits. As new generations of IC products are released, the functionality of these products increases while the number of components used to fabricate them decreases.
ICs are semiconductor devices constructed from silicon (Si), gallium arsenide (GaAs), or other semiconductor material wafers through processes that comprise a large number of deposition, masking, diffusion, etching, and implanting steps. Usually, many individual devices are constructed on the same wafer. When the devices are diced into individual squares or rectangles, each square or rectangle is an IC die.
One or more IC dies are then mounted onto a package substrate in a process called die-attach, electrically connected to the package substrate in a wire or solder bonding operation, encapsulated in a packaging operation, and/or singulated into IC packages. With continuing technology improvements, packages themselves are also achieving higher and higher densities.
Because ICs are becoming smaller, they are more sensitive to particles and debris causing performance problems. The ICs are manufactured in ultra-clean environments to prevent even the smallest contamination. Since the ICs are becoming more sensitive to fine-size debris, more and more processes must be used to clean the ICs, and these chemical processes tend to use chemicals which are expensive or that contaminate the environment.
In the dicing process, protective coatings are often deposited to provide surface protection for the wafers. For ease of removal, the protective coatings are water-soluble. After various manufacturing steps, the material must be removed using high purity de-ionized water washes. As production volumes increase, more of the water-soluble materials must be used and the mixtures disposed of, which substantially increases cost.
In addition, the protective coatings are often spun, sprayed, or dip deposited, which means excess material is often deposited or it is difficult to form uniform coatings. Further, dicing frames accumulate unintentional layers of coating.
Another problem relates to the time consumed for coating and removal, which slows down the production line.
Solutions to these problems have been long sought, but prior developments have not taught or suggested any solutions and, thus, solutions to these problems have long eluded those skilled in the art.